INTERACTION AMONG VITAMIN-C, VITAMIN-E, AND BETA-CAROTENE

The effects of vitamin C (ascorbic acid), vitamin E (alpha-tocopherol) , and beta-carotene as antioxidants and their cooperative action again st the oxidation of lipid in solution, membranes, and lipoproteins hav e been studied and reviewed. Ascorbic acid and alpha-tocopherol act as potent, and probably the most important, hydrophilic and lipophilic a ntioxidants, respectively. They function at their own site individuall y and furthermore act synergistically. beta-Carotene has lower reactiv ity toward radicals than does alpha-tocopherol and acts as a weak anti oxidant in solution. It is more lipophilic than alpha-tocopherol and i s assumed to be present at the interior of membranes or lipoproteins, which enables it to scavenge radicals within the lipophilic compartmen t more efficiently than does alpha-tocopherol. The cooperative interac tion between vitamin C and vitamin E may be quite probable, that of vi tamin C and beta-carotene is improbable, whereas that between vitamin E and beta-carotene may be possible.